London: The cellphone in your pocket can reveal who are your real friends, and how you interact with them, according to a five-year-long study.

The study has opened new possibilities for social scientists, epidemiologists, and other researchers to understand how people connect and interact socially.

Nathan Eagle of the Santa Fe Institute in New Mexico and his colleagues Sandy Pentland of the Massachusetts Institute of Technology and David Lazer of Northeastern University in Boston handed out cellphones to 94 volunteers at MIT.

The phones were modified with software that logged the volunteers' calls, and used Bluetooth to detect when another of the phones was close by.

They looked for simple patterns in the logs of calls and times when phones were close together, and found that it was possible to predict who the volunteers would identify as their friends with 95 per cent accuracy.

For example, being nearby on campus during work hours meant little, but if two phones were close together for several hours on a Saturday evening their owners were likely to be friends. "You can think of it as a behavioural signature," New Scientist quoted Eagle as saying. The scientists could also link the phone data to the volunteers' satisfaction at work.

They found that people who reported themselves to be less satisfied were less likely to have friends in close proximity, and more likely to call friends during work hours. The phones proved more accurate than the volunteers themselves at measuring how much time they spent physically near to others.

It was found that people typically overestimated how much time they spent close to friends, and underestimated how much time they spent with more casual contacts.

Although some of these findings may sound obvious, the study has offered an important proof of principle - the gadgets we carry day-to-day can accurately record the nuances of our relationships.

Using cellphones for social science research could replace interviews, which are laborious and sometimes unreliable, to find out about people's lives.

The cellphone approach may also have immediately practical applications such as helping epidemiologists predict how swine flu will spread from person to person. The study has been published in the Proceedings of the National Academy of Sciences.

SYDNEY: Bacteria can solve complex mathematical problems and may form the building blocks of future supercomputers, according to a new study.

Published in the Journal of Biological Engineering, the proof-of-principle study used glowing bacteria to crack the classic 'Hamilton Path Problem', showing that bacteria can be programmed to do maths.

“Our work demonstrates the potential for using living cells to solve mathematical problems,” said lead researcher Todd Eckdahl, a synthetic biologist at Missouri Western State University in the USA.

Complex mathematical problem

“It supports the view that bacteria can be used to perform computations. Someday, living computers could have applications in medicine, energy, and the environment,” he said.

The Hamilton Path Problem involves working out if a number of connected points on a graph can all be visited, once and only once, using only the existing connections. For example, can you make a car trip visiting Sydney, Melbourne, Alice Springs and Adelaide without leaving the road, or visiting any cities twice?

Although this simple case seems easy to work out, as the number of points increases, the problem becomes much more difficult and time consuming to solve. Current supercomputers would take thousands of years to solve the Hamilton Path Problem with only 20 points, Eckdahl said.

Eckdahl and his team suspected that bacteria might be better at solving this kind of problem than conventional computers. This is because bacteria grow and reproduce very quickly – if you have billions of bacteria working on the same problem in parallel, a solution is likely to evolve, he said.

Coding for colour

Programming the hardware – in this case the bacteria's DNA – is the tricky bit. To see if this was possible, Eckdahl's team programmed some E. Coli cells to solve a simple case using only three points. They modified the bacterial DNA so points were represented as genes which code for colour, with the intervening DNA being the route between points.

These cells were then made to multiply and shuffle their DNA, with different cells representing different solutions to the problem.

Cells which solved half the problem (how to visit two points) glowed either green or red, while cells which had solved the whole problem (how to visit all three cities) glowed both green and red at the same time, causing them to appear yellow. Their DNA was then 'read' to decipher the answer.

It is as though each bacterial computer comes up with an itinerary for the trip and we are looking for one that starts at the first city, ends at the last, and visits the other once,” Eckdahl told Cosmos Online.

Spurred on by this success, he now hopes to use bacteria to solve more complex cases, possibly by using more genes for other colours or antibiotic resistance. He is quick to point out, though, that it will be years before bacteria can out-compete modern computers.

Dinesh Kumar, a bioengineer from the Royal Melbourne Institute of Technology, in Australia, commended the study. “Eckdahl and colleagues have demonstrated the use of bacterial computers to solve a complex problem.”

Kumar added that “this could be extremely useful for a number of biological and social applications, from analysis of social history to finances… such computational power provides the intelligence for the future.”

Washington, Aug 17 (IANS) After more than 50 years of research, scientists have finally discovered a number of new mosquito repellants that keep the dangerous pests away much longer than before.
The new repellants beat DEET, the current gold standard for warding off mosquitoes. DEET is N,N-Diethyl-meta-toluamide, a slightly yellow oil. It is the most common active ingredient in insect repellants.

The new repellants make mosquitoes stay away three times longer than DEET, and without the latter’s odour. Nor does it cause DEET’s sticky-skin sensation.

But there’s a fly in the ointment: The odds may be stacked against any of the new repellants finding a place on store shelves this year or next — or ever.

Ulrich Bernier from the Centre for Medical, Agricultural, and Veterinary Entomology (CMAVE), who led a new study on the subject, said the costly, time-consuming pre-market testing and approval process is a hurdle that will delay availability of the repellants, which were developed last year.

Bernier and his team developed the repellants with what they say is the first successful application of a computer model using the molecular structures of more than 30,000 chemical compounds tested as repellants over the last 60 years.

Using 11 known compounds, they synthesised 23 new ones. Of those, 10 gave about 40 days protection, compared to 17.5 days for DEET, when a soaked cloth was worn by a human volunteer. When applied to the skin, however, DEET lasts about five hours.

“If the mosquitoes don’t even land, we know the repellent is surely working,” he explained. “If they walk around on the cloth-covered-arm, they are on the verge of being repelled. If they bite… on to the next repellent,” Bernier said, according to a CMAVE release.

These results were presented Monday at the 238th National Meeting of the American Chemical Society (ACS).

Washington, Aug 17 (IANS) The mystery of why temperatures in the sun’s outer atmosphere soar to several million degrees, far hotter than temperatures near the sun’s surface, has been solved.
New observations made with instruments aboard Japan’s Hinode satellite reveal the hotter outer atmosphere is due to nanoflares.

Nanoflares are small, sudden bursts of heat and energy. “They occur within tiny strands that are bundled together to form a magnetic tube called a coronal loop,” said James Klimchuk, an astrophysicist at the Goddard Space Flight Centre’s Solar Physics Lab in Maryland.

Coronal loops are the fundamental building blocks of the thin, translucent gas known as the sun’s corona. Scientists previously thought steady heating explained the corona’s million degree temperatures.

The XRT measured plasma at 10 million degrees Kelvin, and the EIS measured plasma at five million degrees Kelvin; 273 degrees Kelvin equal zero degree Celsius.

“These temperatures can only be produced by impulsive energy bursts,” said Klimchuk, who presented the findings at the International Astronomical Union General Assembly meeting in Rio de Janeiro, Brazil.

New Delhi, Aug 17 (IANS) The first dry powder inhalable vaccine for measles will be tested next year in India. Millions of infants and children suffer from the disease which kills almost 200,000 annually.
Robert Sievers, University of Colorado-Boulder (UC-B), who led the team that developed the dry-powder vaccine, said it is a perfect fit for use in developing countries.

Those areas often lack the electricity for refrigeration, clean water and sterile needles needed to administer traditional liquid vaccines.

“Human clinical trials are expected to begin next year in India, after animal safety studies are completed this year” he said.

If the inhaler passes final safety and effectiveness tests, the Serum Institute of India Ltd. expects a demand growing to 400 million doses of measles vaccine a year.

“Childhood vaccines that can be inhaled and delivered directly to mucosal surfaces have the potential to offer significant advantages over injection,” Sievers said.

“Not only might they reduce the risk of infection from HIV, hepatitis, and other serious diseases due to unsterilised needles, they may prove more effective against disease.”

Many serious infections, such as the measles virus, can enter the body through inhalation.

“Measles vaccine dry powders have the potential to effectively vaccinate infants, children and adults by inhalation, avoiding the problems associated with liquid vaccines delivered by injection,” he added.

Although made for developing countries, the technology eventually could become the basis for a new generation of inhalable — and pain free vaccines — in the US and elsewhere. So far, an inhalable vaccine is available for only one disease. It is a wet mist vaccine for influenza.

These findings were presented at the 238th National Meeting of the American Chemical Society (ACS).

Imagine if every time you sent a letter, the postman made a copy. Or whenever you printed photos, the chemist kept a set for himself. This isn’t 1950s Russia but the internet today. Every e-mail you send is stored on not only your computer but also the recipient’s machine; your internet service provider (ISP) will have one too, as will the many servers that have handled your message in its travels across cyberspace. And the government is allowed, under a European commission directive, to dip into some of that data.

It’s this Big Brother vision that has inspired researchers in Seattle to create the world’s first self-destructing e-mails. Vanish, a free program developed by Roxana Geambasu and Professor Hank Levy of Washington University, puts an expiry date on digital messages. Eight hours after being sent, Vanish e-mails become unreadable — even to the person who wrote them.

Levy says his software is a response to the fact that the digital world has forgotten how to forget. “Storage is now incredibly cheap and there’s really no need to delete data any more,” he explains. “Personal data last for a long time.” A recent survey found that a fifth of Americans had written something online that they regretted, while almost one in eight teenagers had posted nude or revealing photos of themselves. In the digital age, these acts remain a permanent, and potentially life-ruining, blot on the record.

Personal e-mails, perhaps containing bank or credit card details, can also linger online for years. “You can’t ensure an e-mail is really deleted because you don’t really control it,” Levy says. “Your e-mail company might store it on back-up tape. A judge could issue a subpoena to get old e-mails or a hacker could break in and steal them. They could be revealed with a system error or someone could simply have their laptop stolen.”

Encrypting your e-mails is no guarantee of privacy, either. In 2007, Hushmail, a company that describes itself as offering the most secure webmail service, admitted to deciphering coded messages and turning them over to Canadian police as part of a drug investigation. In the UK, suspects have been forced to turn over e-mail encryption passwords to the courts or face jail.

Vanish would make such events impossible. Like other encryption programs, the new software scrambles text into a string of nonsensical letters and numbers. Then comes the clever bit: Vanish splits the digital key to decode the message into 10 pieces. These fragments are then hidden in plain sight, on 1.5m randomly selected computers — part of a network of machines spread across more than 200 countries. Not only does this make it almost impossible for hackers to locate the key fragments; it gives Vanish messages their limited lifespan, because as users log off from this network and their computers refresh their memories, the number of key fragments online decreases. After eight hours, on average, enough fragments will have been erased for the message to be unreadable — to the writer, the recipient or a court.

At the moment, Vanish requires both parties in an e-mail or chatroom to install the program and to use the Firefox web browser to communicate. You can then use any webmail service or social network to compose a message, highlight the text you want to keep private, choose “Create Vanish message” from a pop-up menu and send the message as usual. At the other end, recipients see only a page of scrambled text until they select “Read Vanish message”.

That doesn’t mean your message is totally secure. You are still trusting the recipient not to make a copy of the e-mail during its eight-hour existence; and, Levy says, Vanish will not render you invisible to the authorities. “There are government agencies that are big enough to threaten this,” he says. “It’s mainly meant for individuals and individual privacy.”

The makers of Vanish are not standing still, however. The next version will allow users to increase the lifespan of e-mails in multiples of eight hours, allowing users to create messages lasting a day, a weekend or a month.

“We live in a world where it’s possible to remember everything that everyone ever does,” Levy says. Vanish may not make today’s digital world any less scary but at least you can finally forget about old e-mails coming back to haunt you, years — or even days — in the future.

Washington, Aug 11 (IANS) Computer scientists have demonstrated how criminals could hack an electronic voting machine (EVM) and ’steal’ votes using a malicious programming approach that had not been invented when the voting machine was designed.
The team of scientists from the Universites of California, San Diego, Michigan and Princeton employed “return-oriented programming” to force an electronic voting machine to turn against itself.

“Voting machines must remain secure throughout their entire service lifetime, and this study demonstrates how a relatively new programming technique can be used to take control of a voting machine that was designed to resist takeover, but that did not anticipate this new kind of malicious programming,” said Hovav Shacham.

Shacham is professor of computer science at UC San Diego’s (UC-SD )Jacobs School of Engineering and study co-author. His study demonstrates that return-oriented programming can be used to execute vote-stealing computations by taking control of an EVM designed to prevent code injection.

The computer scientists had no access to the machine’s source code - or any other proprietary information - when designing the demonstration attack.

By using just the information that would be available to anyone who bought or stole a voting machine, the researchers addressed a common criticism made against voting security researchers: that they enjoy unrealistic access to the systems they study.

“Based on our understanding of security and computer technology, it looks like paper-based elections are the way to go. Probably the best approach would involve fast optical scanners reading paper ballots. These kinds of paper-based systems are amenable to statistical audits, which is something the election security research community is shifting to,” said Shacham.

“You can actually run a modern and efficient election on paper,” he said.

“If you are using electronic voting machines, you need to have a separate paper record at the very least,” he added.

There findings were presented at the 2009 Electronic Voting Technology Workshop.

Sydney, Aug 7 (IANS) Quantum computing, the latest advance on the technology front that is still hedged with many ifs and buts, may be more stable than previously thought, according to the latest research.
Tom Stace, a University of Queensland (UQ) physicist, found that with even 50 percent loss of components, they could still work, unlike conventional computers, which would have broken down.

“Our results demonstrate that relatively large errors and losses can be tolerated, and so may confirm that quantum computers are genuinely feasible,” Stace said.

“What our work shows is theoretically a useful quantum device can be built even if up to 10 percent of its components suffer an error, or up to 50 percent of the components are completely lost.”

“Quantum devices are very sensitive to noise in their surroundings, and their performance can be greatly impaired by errors. Our research is therefore focussed on how one could build a useful device from imperfect components,” said Stace.

“This theoretical work gives a quantitative idea of how precise quantum engineering needs to be in order to make useful devices.”

Stace said while quantum computing was still in its early days, it had the potential to revolutionize computers because of its potential to be much more powerful than current computers, especially in fields such as banking where security of transactions is paramount.

Berlin, Aug 2 (DPA) The US leads the world in the sending of spam, according to a study.
The study by IT security solutions provider Sophos showed that spam originating in Russia has dropped significantly. It also claimed that some 16.5 percent of all spam mails sent in the second quarter of this year came from the United States.

Russian spammers - previously a highly active bunch - were only responsible for 3.2 percent of all spam sent, which puts them in ninth place on the list.

Second place went to Brazil (11.1 percent), followed by Turkey (5.2) and India (5.0).

Washington, July 28 (IANS) The brain is known to perceive information before it reaches a person’s awareness. Until recently, there was little way to determine what specific mental tasks were taking place prior to the point of conscious awareness.
Now scientists at Rutgers University, Newark and University of California Los Angeles (UCLA), have found a way to use functional magnetic resonance imaging (fMRI), and can peer into the brain to uncover accurately how information is processed before reaching awareness.

“It’s the same principle experienced during a car accident. The car accident actually happens tens of a milliseconds before you are aware you have actually been hit,” explained Stephen Jose Hanson, psychology professor at Rutgers, who led the study.

“By looking at the back of the brain, we can ‘read out’, for example, that a person is looking at dogs and cats before they actually know they are looking at a dog or a cat,” he added.

The research also suggests that a more comprehensive approach is needed for mapping brain activity and that the widely held belief that localized areas of the brain are responsible for specific mental functions is misleading and incorrect.

In the recent past, much of neuroimaging has focussed on pinpointing areas of the brain that are uniquely responsible for specific mental functions, such as learning, memory, fear and love.

But this latest research shows that the brain is more complex than that simple model. In their analysis of global brain activity, the researchers found that different processing tasks have their own distinct pattern of neural connections stretching across the brain, similar to the fingerprints that distinctively identify each of us.

Rather than being a static pattern, however, the brain is able to arrange and rearrange the connections based on the mental task being undertaken.

“You can’t just pinpoint a specific area of the brain, for example, and say that is the area responsible for our concept of self or that part is the source of our morality,” said Hanson.

The findings, based on a study of 130 volunteers, could also pave the way for earlier diagnosis and better treatment of mental disorders, such as autism and schizophrenia, by offering a means for identifying very subtle abnormalities in brain activity and synchrony.

These findings are slated for publication in the October issue of Psychological Science.

London, July 28 (IANS) Scientists have created a transparent form of aluminium by bombarding the metal with the world’s most powerful soft X-ray laser.
The discovery was made possible with the development of a new source of radiation that is 10 billion times brighter than any synchrotron in the world (for example Britain’s Diamond Light Source).

The FLASH laser, based in Hamburg, Germany, produces extremely brief pulses of soft X-ray light, each of which is more powerful than the total output of a plant powering an entire city.

‘Transparent aluminium’ previously only existed in science fiction, featuring in the movie Star Trek IV, but the real material is an exotic new state of matter with implications for planetary science and nuclear fusion.

An international team, led by Oxford University scientists, reported that a short pulse from the FLASH laser ‘knocked out’ a core electron from every aluminium atom in a sample without disrupting the metal’s crystalline structure. This turned the aluminium nearly invisible to extreme ultraviolet radiation.

The Oxford team, along with their international colleagues, focussed all this power down into a spot with a diameter less than a twentieth of the width of a human hair. At such high intensities the aluminium turned transparent.

Whilst the invisible effect lasted for only an extremely brief period — an estimated 40 femtoseconds — it demonstrates that such an exotic state of matter can be created using very high power X-ray sources.

“What we have created is a completely new state of matter nobody has seen before,” said Justin Wark, physics professor at the Oxford University and a study co-author.

“Transparent aluminium is just the start. The physical properties of the matter we are creating are relevant to the conditions inside large planets,” said Wark.

“We also hope that by studying it we can gain a greater understanding of what is going on during the creation of ‘miniature stars’ created by high-power laser implosions, which may one day allow the power of nuclear fusion to be harnessed here on Earth,” he added.

Wark added: “What is particularly remarkable about our experiment is that we have turned ordinary aluminium into this exotic new material in a single step by using this very powerful laser.”

Addis Ababa, July 26 (IANS) A long-expected fibre-optic cable linking southern and eastern Africa to global telecommunications networks via India and Europe has gone live with high expectations it will lower the cost of telecommunications in Africa. Its switch-on date was delayed for a month after threats by Somali pirates along the Indian Ocean route from India to Kenya disrupted cable installation plans.

The cable has simultaneously launched in Kenya, Tanzania, Mozambique, South Africa and Uganda on July 23. It is widely seen to be opening up opportunities for governments and business to use the network as a platform to compete globally and drive economic growth.

Backhauls linking Johannesburg, Nairobi, and Kampala with coastal landing stations have also been established. Additionally, SEACOM, the fibre-optic company behind the operation, is working with national partners to commission the final link to Kigali, Rwanda, and Addis Ababa, Ethiopia.

The US$600 million cable has direct connections to India and from India to Europe, making it the first cable to hook east and southern Africa to India and Europe. The 17,000 kilometer cable has a capacity of transmitting data amounting to 1.28 terrabytes per second.

According to reports, SEACOM management is marking the launch of the cable with a one gigabytes per second live international connection and live high-definition video feed over an IP network to interconnect representatives and dignitaries across the five African countries.

The Common market for Eastern and Southern Africa (Comesa) Secretary General Sindiso Ngwenya said that most countries in the Comesa region will connect to the cable for broadband services.

“In fact [in the] Comesa region, we are constructing a fiber cable called the Lower Indian Ocean Network under the Indian Ocean that will connect to the SEACOM cable for broadband services to our member countries,” Ngwenya said.

Many other countries in the Comesa region, Ngwenya said, are developing inland cables that will soon be connected to the SEACOM cable.

Comesa is a regional economic bloc, which has more than 19 member countries including Kenya, Mozambique, Zambia, Ethiopia Rwanda and Uganda, and is chartered to accelerate the region’s economy through improved communication and business.

Broadband connectivity means the region will have no problems linking to medical and education institutions in India for telemedicine and tele-education, Ngwenya said.

The SEACOM cable, which is privately funded and three-quarters African owned, is expected to provide bandwidth on an open access basis, allowing all operators to have equal access to the cable.

African countries currently rely on expensive and slow satellite connection for telephones and the Internet.

Washington, July 25 (IANS) Researchers have programmed a virulent microbe, the E. coli, to potentially solve complicated mathematics problems.
The researchers have found that computing in living cells is feasible, opening the door to a number of applications.

The second-generation bacterial computers illustrate the feasibility of extending the approach to other computationally challenging maths problems.

A research team comprising four faculty members and 15 biology and maths undergraduates from Missouri Western State University (MWSU) and Davidson College in North Carolina engineered the DNA of E. coli.

They were able to create bacterial computers capable of solving a classic mathematical problem known as the Hamiltonian Path Problem.

The Hamiltonian Path Problem asks whether there is a route in a network from a beginning node to an end node, visiting each node exactly once.

The researchers modified the genetic circuitry of the bacteria to enable them to find a Hamiltonian path in a three-node graph.

Bacteria that successfully solved the problem reported their success by fluorescing both red and green, resulting in yellow colonies.

Synthetic biology is the use of molecular biology techniques, engineering principles, and mathematical modelling to design and construct genetic circuits that enable living cells to carry out novel functions, said a MWSU release.

“The research provides yet another example of how powerful and dynamic synthetic biology can be. We used synthetic biology to solve mathematical problems; others find applications in medicine, energy and the environment. Synthetic biology has great potential in the real world,” said Jordan Baumgardner, recent graduate of Missouri Western and study co-author.

Hamburg, July 20 (DPA) The most intense X-ray beam of its type in the world has been generated inside a 2,300-metre circular tunnel under the German city of Hamburg, the Desy research institute said Monday.
The machine, which cost 225 million euros ($297 million), was switched on in April, but unlike a light bulb it takes weeks to tune up.

The X-ray light came Saturday. More months will now be spent adjusting measuring devices. Next year, scientists can begin actually using the machine to peer at atomic structures in proteins, cancer cells and the like.

Earlier this year, India signed an agreement to aid the project and gain special access to the machine, known as a synchrotron, which has been remodelled from an earlier particle accelerator at the site and is named Petra III.

In a previous life, the Petra ring was used to discover an atomic particle called the gluon.

The synchrotron keeps a beam of up to 10 billion positrons - the anti-particles to electrons - going round a circle permanently at almost the speed of light.

Desy, which is mainly funded by the German government, said the particles had been racing round the tracks for weeks, but have now been put on a zig-zag course so that they emit the light needed for experiments.

Washington, July 16 (IANS) Birds, deer, monkeys and other wild animals all bark — but why are dogs more vocal than others?
The reason is related to dogs’ 10,000-year history of hanging around human food refuse dumps, says evolutionary biologist Kathryn Lord, University of Massachusetts (U-M).

Lord and co-authors also provide scientific literature with its first consistent, functional and acoustically precise definition of this common animal sound.

“We suggest an alternative hypothesis to one that many biologists seem to accept lately, which seeks to explain dog barking in human-centric terms and define it as an internally motivated vocalization strategy,” explains Lord who led the study.

In the researchers’ view, however, barking is not a special form of communication between dogs and humans. “What we’re saying is that the domestic dog does not have an intentional message in mind, such as, ‘I want to play’ or ‘the house is on fire,’” said Lord.

Rather, she and colleagues say barking is the auditory signal associated with an evolved behaviour known as mobbing, a cooperative anti-predator response usually initiated by one individual who notices an approaching intruder.

A dog barks because it feels an internal conflict; an urge to run plus a strong urge to stand its ground and defend pups, for example. When the group joins in, the barks intimidate the intruder, who often flees.

“We think dogs bark due to this internal conflict and mobbing behaviour, but domestic dogs bark more because they are put, and put themselves into, conflicting situations more often,” she says.

The reason traces back to the first dogs that started hanging around human food dumps about 8,000 to 10,000 years ago.

They would have experienced a serious disadvantage if they had run a mile away every time a human or other animal approached.

“In evolutionary terms, dogs self-selected the behaviour of sticking around, overcoming their fear and being rewarded by getting to eat that meal before some other dog got it,” Lord said.

“Thus these animals allow people to get unusually close. The scared ones die while those less scared stay, eat, survive and reproduce. So they inherit the tendency.”

These findings were published in a special issue of Behavioural Processes

Washington, July 16 (IANS) The accidental discovery of a bowl-shaped molecule that pulls carbon dioxide out of the air paves the way for exciting new possibilities to deal with global warming.
These possibilities include genetically engineering microbes to manufacture those carbon dioxide “catchers”, said J.A. Tossell, a Maryland University scientist who led the study.

He noted that another scientist discovered the molecule while doing research unrelated to global climate change.

Carbon dioxide was collecting in the molecule, and the scientist realised that it was coming from air in the lab. Tossell recognised that these qualities might make it useful as an industrial absorbent for removing carbon dioxide.

Tossell’s new computer modelling studies found that the molecule might be well-suited for removing carbon dioxide directly from air, in addition to its previously described potential use as an absorbent for carbon dioxide from electric power plants and other smoke stacks.

“It is also conceivable that living organisms may be developed which are capable of replacing structurally ion receptors within their cell membranes,” the report noted.

These findings are slated for publication in the Aug 3 issue of Inorganic Chemistry

Washington: A team of scientists has built synthetic glass leafs that would sweat to generate electricity.

According to a report in New Scientist, the new synthetic leaves were developed by Michel Maharbiz at the University of California, Berkeley, working with colleagues at the University of Michigan and MIT.

They built their leaves from glass wafers shot through with a branching network of tiny water-filled channels arranged like the veins of a leaf.

The smaller channels extend to the edge of the plate and have open ends that allow water to evaporate, drawing fluid along the leaf's central stem at a rate of 1.5 centimeters per second.

The researchers added metal plates to the walls of the central stem and connected them to a circuit.

The charged plates and the water within the stem create a sandwich of two conducting layers separated by an insulating layer - in effect, a capacitor.

The leaf is transformed into a source of power by periodically interrupting the water flowing into the leaf with air bubbles.

Thanks to the different electrical properties of air and water, every time a bubble passes between the plates the capacitance of the device changes and a small electric current is generated, which passes to an external circuit where it's used to pump up the voltage on a storage capacitor.

"We use the mechanical energy in the liquid flow to change the capacitance and add energy to the capacitor," said Maharbiz.

Each bubble results in an increase in output voltage of some 2 to 5 microvolts, and the device has a power density of some 2 microwatts per cubic centimetre.

"I think we could easily reach hundreds of microwatts per cubic centimetre (with modifications)," he said.

That is still a fraction of the power density of power systems such as fuel cells or batteries, but it's a respectable figure for an energy scavenging system, according to Maharbiz.

The device could be scaled up to produce artificial trees that generate power entirely through evaporation wherever there's a cyclical change in humidity.

Although the modest power output is not enough to rival solar technology, Maharbiz thinks it could act as a complementary technology.

The sunlight that generates solar power could also drive transpiration to boost the electricity generated.

Washington: Researchers at the Johns Hopkins School of Medicine, US, have discovered in fish yet another type of cell that can sense light and contribute to vision.

The team of neuroscientists shows that retinal horizontal cells, which are nerve cells once thought only to talk to neighboring nerve cells and not even to the brain, are light sensitive themselves.

"This is mind-boggling," said King-Wai Yau, a professor of neuroscience at the Solomon H. Snyder Department of Neuroscience at Johns Hopkins.

"For more than 100 years, it's been known that rod cells and cone cells are responsible for sensing light, and therefore, vision," said Yau.

"Then, about seven years ago, another light sensor was discovered in the retina, revealing a third type of light-sensitive cells in mammals, so we set out to look at whether this was true in other vertebrates as well," he added.

Focusing their efforts on the melanopsin light sensor, which is responsible for sensing day and night but barely involved - in mammals, at least - in seeing images, Yau's team looked for melanopsin-containing cells in other vertebrates, and found some in the retinal horizontal cells in goldfish and catfish.

Catfish contain two flavors of retinal horizontal cells: those that connect to cone cells, which respond to bright light, and those that connect to rod cells, which respond to dim light.

The team took electrical readings from single isolated retinal horizontal cells.

They found that light caused a change in electrical current in cone horizontal cells but not in rod horizontal cells.

According to Yau, horizontal cells allow cross-talk between neighboring photoreceptor cells, allowing these cells to compare the light they sense, a process necessary for the brain to see images.

"The brain processes what it sees in context to the surroundings," said Yau. "This allows our brain to see borders and contours-horizontal cells are the reason why we can recognize and see a face, for example," he added.

Testing light at different wavelengths, the team found that these fish horizontal cells are thousands of times less light sensitive than their partner cone cells.

"The bottom line is that the light effect on the horizontal cells is subtle, perhaps to allow the eyes of these animals to fine-tune their functions to different ambient light conditions," said Yau.

"But that these horizontal cells are light sensitive at all is a very surprising finding and changes how we think about retinas as a whole," he added.

Washington: What is being expected to prove the most powerful computer of its kind in the world became operational at the University of Florida this week.

The supercomputer has been named 'Novo-G' by its designers . The first part of its name came from the Latin term for "make anew, change, alter", and the second from "G" for "genesis".

It is a "reconfigurable" computer that can rearrange its internal circuitry to suit the task at hand.

Alan George, professor of electrical and computer engineering and director of UF's National Science Foundation Center for High-Performance Reconfigurable Computing, says that applications may range from space satellites to research supercomputers -- anywhere size, energy and high speed are important.

Traditional computers use so-called "fixed logic devices" to perform a large variety of tasks, but this approach requires a substantial amount of overhead in space and energy, no matter what work needs to be done.

While special-purpose computers can be built to perform certain tasks very well, they are not flexible.

According to George, reconfigurable computers make the best of both worlds because they can rearrange their internal circuitry like Lego blocks to create the most appropriate architecture for each assignment, and, thus, can be from 10 to 100 times faster than other computers their size, while using five to 10 times less energy.

Although the concept has been proven, reconfigurable computers remain at the research stage and are not easy to use. One of the main goals of the NSF Center is to pioneer techniques to make reconfigurable computers more accessible.

"It is very powerful technology, but it is also very complicated technology. We don't want this important technology to be accessible only to experts," George said.

The University of Florida has three partner universities in its reconfigurable computing center -- Brigham Young University, George Washington University and Virginia Tech.

LOS ANGELES (Reuters) - The amino acid glycine, a fundamental building block of proteins, has been found in a comet for the first time, bolstering the theory that raw ingredients of life arrived on Earth from outer space, scientists said on Monday.

Microscopic traces of glycine were discovered in a sample of particles retrieved from the tail of comet Wild 2 by the NASA spacecraft Stardust deep in the solar system some 242 million miles (390 million km) from Earth, in January 2004.

Samples of gas and dust collected on a small dish lined with a super-fluffy material called aerogel were returned to Earth two years later in a canister that detached from the spacecraft and landed by parachute in the Utah desert.

Comets like Wild 2, named for astronomer Paul Wild (pronounced Vild), are believed to contain well-preserved grains of material dating from the dawn of the solar system billions of years ago, and thus clues to the formation of the sun and planets.

The initial detection of glycine, the most common of 20 amino acids in proteins on Earth, was reported last year, but it took time for scientists to confirm that the compound in question was extraterrestrial in origin.

"We couldn't be sure it wasn't from the manufacturing or the handling of the spacecraft," said astrobiologist Jamie Elsila of NASA's Goddard Space Flight Center in Greenbelt, Maryland, the principal author of the latest research.

She presented the findings, accepted for publication in the journal Meteoritics and Planetary Science, to a meeting of the American Chemical Society in Washington, D.C., this week.

"We've seen amino acids in meteorites before, but this is the first time it's been detected in a comet," she said.

Chains of amino acids are strung together to form protein molecules in everything from hair to the enzymes that regulate chemical reactions inside living organisms. But scientists have long puzzled over whether these complex organic compounds originated on Earth or in space.

The latest findings add credence to the notion that extraterrestrial objects such as meteorites and comets may have seeded ancient Earth, and other planets, with the raw materials of life that formed elsewhere in the cosmos.

"The discovery of glycine in a comet supports the idea that the fundamental building blocks of life are prevalent in space, and strengthens the argument that life in the universe may be common rather than rare," said Carl Pilcher, the director of the NASA Astrobiology Institute in California, which co-funded the research.

Glycine and other amino acids have been found in a number of meteorites before, most notably one that landed near the town of Murchison, Australia in 1969, Elsila said.